With the increase in independent telephone companies and local equipment, concerns have been raised as to responsibilities for operational problems. The company controlling the telephone lines in service must decide whether or not a fault is in its portion of the system or rather in the equipment and wiring which is provided by the homeowner or businessman, or by a local, independent vendor. When virtually all portions of the system and service are provided by the same company and a fault (service interruption) occurs, neither the user nor the telephone company is initially concerned as to precisely where in the system the fault is located. A user knows who to call and the service technician knows that the entire system is his responsibility to check out, identify the fault and institute a repair. It matters not whether there is a loss of continuity to the incoming lines or if a piece of equipment inside the home or business has malfunctioned, there is only one company to call.
Once the service or repair technician arrives, the location or source of the fault becomes of concern, but not until then. The obvious advantage of a single provider for all services, as well as all equipment is that "fault" service runs are not made by the wrong company. However, the opening up of the telephone industry by recent legislative and court actions has brought forth numerous equipment providers who simply tie into the main incoming telephone lines which are the responsibility of another company. It is a reality of this commercial setting that split service will continue to exist and thus some means is needed to allow a local user to determine which part of the system is responsible for a service interruption. If a device could be provided at the point of demarcation between the wiring and equipment responsibilities of the two companies, which device would indicate the portion of the wiring and equipment responsible for the fault, it would be a significant advantage over what presently exists, which is virtually nothing.
The present invention provides such a device and while line testing and continuity devices presently exist, there is nothing believed to exist that is structured or functions as does the present invention. Two such line testing devices are disclosed by two patents issued to Ahuja. U.S. Pat. No. 4,369,341 issued Jan. 18, 1983 and U.S. Pat. No. 4,388,501 issued June 14, 1983. Both of these patents pertain to a line test termination device for use as part of a telephone system. The U.S. Pat. No. 4,369,341 is designed for use on a telephone subscriber line and structured to permit a subscriber test to indicate the operability of the subscriber line. The associated circuitry is more complex than that of the present invention, and this particular patent follows not only a different approach, but tries to achieve different results.
U.S. Pat. No. 4,388,501 discloses an audio-visual line test termination device providing a characteristic signature to the telephone central office and a visual and audible signal to the customer when a continuity test is made on a subscriber line. Both of the patent references listed require, according to their disclosure, a 100-volt test current which must be applied by a telephone company employee. In the present invention, identification of system faults is not dependent on the making of a continuity test, all service interruption faults are instantly identified as well as enabling an indication as to what portion of the wiring and equipment is responsible for the fault.
The present invention provides a visually distinguishable point of demarcation for a local telephone company network access line. Secondly, the visual display which is provided by the present invention enables the user to make an indication of the integrity of the network access line while in an idle condition. Thirdly, the visual display of the present invention aids the user in identifying most electrical faults and determining whether or not the fault is in the local telephone company or the user portion of the circuit. Finally, the present invention provides an electrically testable circuit which will aid the local telephone company in determining continuity of the network access line into a user's premises.
Each of these characteristics will be described in greater detail hereinafter. The structure of the device which provides these operational abilities is novel and unobvious and an improvement over whatever may exist in this area of technology.